Can you find sound not working for any other programs? If not, the problem may be only related to those programs. By sound, do you mean all sound, or just sound from specific sources (streaming format, CD, etc.)?

I'm not familiar with kaffeine, but it looks to me like the problem is indeed kaffeine, as opposed to a more system-wide problem. I suspect you should not be getting all these warnings and errors, especially the ones telling you that kaffeine may misbehave.

The sound in both programs stopped to work after a huge emerge when I came back from hollidays. 7 weeks of updates.
I will be hard to find where it come from.

What's the relation between Kafffeine and Totem ? Kaffeine is from KDE and I think Totem comes from Gnome...
How do they connect to the sound system, using ALSA, or other program ?_________________Linux, cause booting is for adding new hardware

Totem and Kaffeine use pulseaudio, mplayer and firefox flash plugin does (apparently) not.
I read the pulseaudio wiki page http://en.gentoo-wiki.com/wiki/PulseAudio and found that the sound device was locked by some program